About 6 days ago I decided to start working out again with a friend and we ended up running 2 miles together on the local school's track, everything was fine. Last night I went back and ran another 2 miles - I woke up in the middle of the night to go to the bathroom and I couldn't walk. My knees hurt so bad - there was a shock of pain in my knees when lifting my feet off the ground.
Now the pain is a little bit less, but still hard to walk.
Is this normal?